Re: [Tarantool-patches] [PATCH v2 2/3] cfg: support symbolic evaluation of replication_synchro_quorum

[Cyrill Gorcunov <gorcunov@gmail.com>]

On Wed, Nov 25, 2020 at 03:46:04PM +0300, Serge Petrenko wrote:
> 
> 25.11.2020 15:12, Cyrill Gorcunov пишет:
> > On Wed, Nov 25, 2020 at 03:04:07PM +0300, Serge Petrenko wrote:
> > > Just noticed. Looks like this diag_set and the one below are ignored:
> > > ```
> > > tarantool> a=string.rep('n', 1000)
> > > ---
> > > ...
> > > 
> > > tarantool> box.cfg{replication_synchro_quorum=a}
> > > ---
> > > - error: 'Incorrect value for option ''replication_synchro_quorum'': the
> > > value must
> > >      be greater than zero and less than maximal number of replicas'
> > > ...
> > Indeed. Actually if you remember I've been using errno for such errors.
> > Now we either should call diag_log() right after diag_set or return
> > errno handling?
> Why? Every time eval returns a value < 0 this means an error.
> Just add a check to check_replication_synchro_quorum.
> eval's return value is ignored here, and diag is rewritten with an unrelated
> error.

iow, you mean something like this?
---
static int
box_check_replication_synchro_quorum(void)
{
	int quorum = 0;

	if (!cfg_isnumber("replication_synchro_quorum")) {
		int value = replicaset.registered_count;
		quorum = box_eval_replication_synchro_quorum(value);
-->		if (quorum < 0)
-->			return -1;
	} else {
		quorum = cfg_geti("replication_synchro_quorum");
	}

	if (quorum <= 0 || quorum >= VCLOCK_MAX) {
		diag_set(ClientError, ER_CFG, "replication_synchro_quorum",
			 "the value must be greater than zero and less than "
			 "maximal number of replicas");
		return -1;
	}
	return quorum;
}